The production of speech sounds involves the control of multiple articulators within the vocal tract. Movements of the velopharyngeal mechanism must be coordinated with the other articulators (e.g. lip, jaw, larynx) and the respiratory system in order to produce perceptually adequate speech output. This project is devoted to study of the form and function of the velophayyngeal mechanism In spite of the work that we have completed, there continues to be a need for anatomical and physiological research to identify normal patterns of velopharyngeal motion, the role of various muscles in controlling this motion, and the gross and fine anatomy of the velopharyngeal region. Not until a comprehensive understanding of all of these aspects of velopharyngeal form and function is attained will we be able to a) understand the normal complex process of speech articulation, and b) fully appreciate the consequences and possible rehabilitative options associated with "damaged" velopharyngeal mechanisms. Our proposed efforts are grouped into four areas of study. The first area represents a continuation of ongoing work in our laboratory directed towards understanding the dynamics and kinematics of velar movements. A second area focuses on interactions between the velopharyngeal mechanism and other articulators, especially the larynx. The third area of study continues and expands our anatomical studies of the tissue composition of the palate and velopharyngeal regions on a histological level. Finally, we plan to initiate finite element modelling of the velopharyngeal mechanism for speech simulation. Our goal is to bring together the body of data collected to date regarding various aspects of velopharyngeal anatomy and physiology and to utilize our experience with finite element modelling of the larynx to develop a quantitative model of velopharyngeal function, such as those attempted for the tongue (Kakita et al., 1985; Wilhelms- Tricarico, 1994) and lips (Muller et al., 1984).